1. Field of the Invention
The present invention relates to typing stations and, more particularly, is directed toward remote typing stations for information storage and retrieval systems.
2. Description of the Prior Art
U.S. Pat. No. 4,260,854 describes an information storage and retrieval system which provides multiple dictation inputs and retrieval outputs to users. Typically, hard-copy transcription of audio reports is carried out by a pool of centrally located typists who have access to and control over the audio reports which have been previously stored in the system. The audio is controlled by sending dual tone multiple frequency (DTMF) tone bursts over one line and the audio is heard coming in on another line. Since this is analog transmission in both directions (normal telephone usage), there is no problem so long as transmission is over two telephone lines. This method is adequate when copies are distributed directly from the local typewriter to the user community. However, for various reasons, it is often advantageous to have the typist sit at a remote terminal and input the transcribed copy directly to a computer through the use of a modem and a terminal. The hard copy of the transcribed data is presented at a central distribution point where it can be edited, printed, and distributed. The problem with this scheme is that while the telephone line is being used for data communications with the computer, it is not normally available for transmission of audio messages. In the data transmission mode, there is a carrier on the telephone line which is frequency shifted for the transfer of data. This operation would not tolerate any analog information on the same line at the same time. U.S. Pat. Nos. 3,648,249; 4,221,938; 4,301,525; 4,303,998 and 4,319,337 disclose dictating systems having central recording units that communicate with remote dictating and transcribing stations.